1. Field
The present disclosure relates to car seats. More particularly, the present disclosure relates to safety car seats. The safety car seats may be for infants or children, although this application is not limited thereto.
2. State of the Art
The most common cause of death for children aged 1-5 in developed countries is by accident, and the leading cause of death by accident is due to car accidents. When properly installed in passenger cars, child safety seats have been reported to reduce fatal injury by about 71% for children under age one and by about 54% for toddlers aged 1-4. Nonetheless, in the U.S. alone, over 250 children aged 0-4 are fatally injured every year while properly restrained in their car seats.
In addition, to the fatalities, every year, thousands of children who are properly restrained in car seats still sustain incapacitating injuries resulting from car accidents. By far the most common severe injuries are head injuries, including cerebrum injuries (contusions or lacerations), concussions, skull vault and skull base fractures, subarachnoid hemorrhages, and subdural hematomas. Other common severe injuries are thoracic (lung and rib), abdominal (bowel, liver, spleen, kidney), spine, and upper extremity (clavicle, humerus, radius/ulna) and lower extremity (pelvis, femur, tibia/fibula) injuries. The injury outcome in children can be worse than similar injuries sustained by adults, and children who suffer traumatic brain injuries can experience lasting or late-appearing neuropsychological problems. For example, frontal lobe functions develop relatively late in a child's growth, so that injury to the frontal lobes may not become apparent until the child reaches adolescence.
According to the U.S. National Highway Traffic and Safety Administration (NHTSA), children under the age of one should always ride in a rear-facing car seat that has a harness. While it is recommended that rear-facing seats be used as long as possible, it is recognized that children aged 1 and over will wish to face forward. NHTSA recommends that children aged 1-3 (and older if they have not reached a certain height and weight) use a forward-facing car seat with a harness and tether that limits the child's forward movement during a crash.
There are many types of car seats available for purchase. Infant seats recommended for children under age 1 are typically rear-facing. Many include a base that is belted or tethered into the car and a seat that can latch into the base. The seat often includes a handle so that the seat may be carried when it is unlatched from the base (i.e., from the car). A popular car seat option for infants as well as children is a “convertible” car seat that may be oriented in a rear-facing position and the “converted” to a front-facing position. Some convertible car seats may even convert into a booster seat for children weighing up to 100 pounds. Typically the convertible car seats are strapped into the car using the car seat-belt, or are anchored to the car frame directly using a LATCH (Lower anchors and Tethers for children) system. All car seats offer a harness for strapping the child into the seat. The usual harness is a five-point safety harness. The car seats tend to be formed from injection molded plastic, typically at least 5 mm thick, and the seats (with base in the case of the infant seats) typically weigh 7 kgs or more.
ISOFIX (ISO standard 13216) is the international standard for attachment points for child safety seats in passenger cars. The system has various other regional names including LATCH (“Lower Anchors and Tethers for Children”) in the United States and LUAS (“Lower Universal Anchorage System”) or Canfix in Canada. It has also been called the “Universal Child Safety Seat System” or UCSSS.
ISOFIX relates to the anchoring system for Group 1 child safety seats. It defines standard attachment points to be manufactured into cars, enabling compliant child safety seats to be quickly and safely secured. ISOFIX is an alternative to securing the seat with seat belts. Seats are secured with a single attachment at the top (top tether) and two attachments at the base of each side of the seat. The full set of anchor points for this system were required in new cars in the United States starting in September 2002.
In the EU the system is known as ISOFIX and covers both Group 0/0+ and Group 1 child safety seats. The mechanism for attaching the seat to the Lower Anchors is quite different from that in the United States. In the EU two “alligator-like” clips connect the seat to the Lower Anchors rather than the open clip style connectors commonly used in the United States. However, some car seat manufactures are beginning to offer true ISOFIX type attachments in the U.S. In the European standard, there are also various installation categories: “universal”, “vehicle-specific” and “semi-universal”. The main difference is that “Universal” represents use of a top tether strap with the ISOFIX anchorage, “vehicle-specific” represents the usage of the ISOFIX anchorage without the Top Tether in specified vehicles only, while “Semi-Universal” represents usage of the ISOFIX anchorage together with a “foot-prop”.